1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <utility> 11 12 // template <class T> 13 // typename conditional 14 // < 15 // !is_nothrow_move_constructible<T>::value && is_copy_constructible<T>::value, 16 // const T&, 17 // T&& 18 // >::type 19 // move_if_noexcept(T& x); 20 21 #include <utility> 22 23 class A 24 { 25 A(const A&); 26 A& operator=(const A&); 27 public: 28 29 A() {} 30 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 31 A(A&&) {} 32 #endif 33 }; 34 35 struct legacy 36 { 37 legacy() {} 38 legacy(const legacy&); 39 }; 40 41 int main() 42 { 43 int i = 0; 44 const int ci = 0; 45 46 legacy l; 47 A a; 48 const A ca; 49 50 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 51 static_assert((std::is_same<decltype(std::move_if_noexcept(i)), int&&>::value), ""); 52 static_assert((std::is_same<decltype(std::move_if_noexcept(ci)), const int&&>::value), ""); 53 static_assert((std::is_same<decltype(std::move_if_noexcept(a)), A&&>::value), ""); 54 static_assert((std::is_same<decltype(std::move_if_noexcept(ca)), const A&&>::value), ""); 55 #else // _LIBCPP_HAS_NO_RVALUE_REFERENCES 56 static_assert((std::is_same<decltype(std::move_if_noexcept(i)), const int>::value), ""); 57 static_assert((std::is_same<decltype(std::move_if_noexcept(ci)), const int>::value), ""); 58 static_assert((std::is_same<decltype(std::move_if_noexcept(a)), const A>::value), ""); 59 static_assert((std::is_same<decltype(std::move_if_noexcept(ca)), const A>::value), ""); 60 #endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES 61 static_assert((std::is_same<decltype(std::move_if_noexcept(l)), const legacy&>::value), ""); 62 63 #if _LIBCPP_STD_VER > 11 64 constexpr int i1 = 23; 65 constexpr int i2 = std::move_if_noexcept(i1); 66 static_assert(i2 == 23, "" ); 67 #endif 68 69 } 70
